Publications by authors named "Rebecca E A Walwyn"

9 Publications

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A hypothesis test of feasibility for external pilot trials assessing recruitment, follow-up, and adherence rates.

Stat Med 2021 Jun 14. Epub 2021 Jun 14.

Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, UK.

The power of a large clinical trial can be adversely affected by low recruitment, follow-up, and adherence rates. External pilot trials estimate these rates and use them, via prespecified decision rules, to determine if the definitive trial is feasible and should go ahead. There is little methodological research underpinning how these decision rules, or the sample size of the pilot, should be chosen. In this article we propose a hypothesis test of the feasibility of a definitive trial, to be applied to the external pilot data and used to make progression decisions. We quantify feasibility by the power of the planned trial, as a function of recruitment, follow-up, and adherence rates. We use this measure to define hypotheses to test in the pilot, propose a test statistic, and show how the error rates of this test can be calculated for the common scenario of a two-arm parallel group definitive trial with a single normally distributed primary endpoint. We use our method to redesign TIGA-CUB, an external pilot trial comparing a psychotherapy with treatment as usual for children with conduct disorders. We then extend our formulation to include using the pilot data to estimate the standard deviation of the primary endpoint and incorporate this into the progression decision.
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http://dx.doi.org/10.1002/sim.9091DOI Listing
June 2021

Bayesian design and analysis of external pilot trials for complex interventions.

Stat Med 2021 05 17;40(12):2877-2892. Epub 2021 Mar 17.

Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, UK.

External pilot trials of complex interventions are used to help determine if and how a confirmatory trial should be undertaken, providing estimates of parameters such as recruitment, retention, and adherence rates. The decision to progress to the confirmatory trial is typically made by comparing these estimates to pre-specified thresholds known as progression criteria, although the statistical properties of such decision rules are rarely assessed. Such assessment is complicated by several methodological challenges, including the simultaneous evaluation of multiple endpoints, complex multi-level models, small sample sizes, and uncertainty in nuisance parameters. In response to these challenges, we describe a Bayesian approach to the design and analysis of external pilot trials. We show how progression decisions can be made by minimizing the expected value of a loss function, defined over the whole parameter space to allow for preferences and trade-offs between multiple parameters to be articulated and used in the decision-making process. The assessment of preferences is kept feasible by using a piecewise constant parametrization of the loss function, the parameters of which are chosen at the design stage to lead to desirable operating characteristics. We describe a flexible, yet computationally intensive, nested Monte Carlo algorithm for estimating operating characteristics. The method is used to revisit the design of an external pilot trial of a complex intervention designed to increase the physical activity of care home residents.
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http://dx.doi.org/10.1002/sim.8941DOI Listing
May 2021

Effectiveness of Dementia Care Mapping™ to reduce agitation in care home residents with dementia: an open-cohort cluster randomised controlled trial.

Aging Ment Health 2020 Apr 13:1-14. Epub 2020 Apr 13.

Clinical Trials Research Unit, Leeds Institute of Clinical Trials Research, University of Leeds, Leeds, UK.

Agitation is common and problematic in care home residents with dementia. This study investigated the (cost)effectiveness of Dementia Care Mapping™ (DCM) for reducing agitation in this population. Pragmatic, cluster randomised controlled trial with cost-effectiveness analysis in 50 care homes, follow-up at 6 and 16 months and stratified randomisation to intervention ( = 31) and control ( = 19). Residents with dementia were recruited at baseline ( = 726) and 16 months ( = 261). Clusters were not blinded to allocation. Three DCM cycles were scheduled, delivered by two trained staff per home. Cycle one was supported by an external DCM expert. Agitation (Cohen-Mansfield Agitation Inventory (CMAI)) at 16 months was the primary outcome. DCM was not superior to control on any outcomes (cross-sectional sample  = 675: 287 control, 388 intervention). The adjusted mean CMAI score difference was -2.11 points (95% CI -4.66 to 0.44,  = 0.104, adjusted ICC control = 0, intervention 0.001). Sensitivity analyses supported the primary analysis. Incremental cost per unit improvement in CMAI and QALYs (intervention vs control) on closed-cohort baseline recruited sample ( = 726, 418 intervention, 308 control) was £289 and £60,627 respectively. Loss to follow-up at 16 months in the original cohort was 312/726 (43·0%) mainly (87·2%) due to deaths. Intervention dose was low with only a quarter of homes completing more than one DCM cycle. No benefits of DCM were evidenced. Low intervention dose indicates standard care homes may be insufficiently resourced to implement DCM. Alternative models of implementation, or other approaches to reducing agitation should be considered.
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http://dx.doi.org/10.1080/13607863.2020.1745144DOI Listing
April 2020

The Implementation of Dementia Care Mapping in a Randomized Controlled Trial in Long-Term Care: Results of a Process Evaluation.

Am J Alzheimers Dis Other Demen 2019 09 5;34(6):390-398. Epub 2019 May 5.

2 Clinical Trials Research Unit, University of Leeds, Leeds, United Kingdom.

This study explored intervention implementation within a pragmatic, cluster randomized controlled trial of Dementia Care Mapping™ (DCM) in UK care homes. DCM is a practice development tool comprised of a 5 component cycle (staff briefing, mapping observations, data analysis and reporting, staff feedback, and action planning) that supports delivery of person-centered care. Two staff from the 31 intervention care homes were trained in DCM and asked to deliver 3 cycles over a 15-month period, supported by a DCM expert during cycle 1. Implementation data were collected after each mapping cycle. There was considerable variability in DCM implementation fidelity, dose, and reach. Not all homes trained 2 mappers on schedule, and some found it difficult to retain mappers. Only 26% of homes completed more than 1 cycle. Future DCM trials in care home settings should consider additional methods to support intervention completion including intervention delivery being conducted with ongoing external support.
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http://dx.doi.org/10.1177/1533317519845725DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6676338PMC
September 2019

Developing and feasibility testing of data collection methods for an economic evaluation of a supported selfmanagement programme for adults with a learning disability and type 2 diabetes.

Pilot Feasibility Stud 2018 23;4:80. Epub 2018 Apr 23.

1Academic Unit of Health Economics, Leeds Institute of Health Sciences, University of Leeds, Worsley Building, Leeds, LS2 9NL UK.

Background: The challenges of conducting research with hard to reach vulnerable groups are particularly pertinent for people with learning disabilities. Data collection methods for previous cost and cost-effectiveness analyses of health and social care interventions targeting people with learning disabilities have relied on health care/health insurance records or data collection forms completed by the service provider rather than by people with learning disabilities themselves. This paper reports on the development and testing of data collection methods for an economic evaluation within a randomised controlled trial (RCT) for a supported self-management programme for people with mild/moderate learning disabilities and type 2 diabetes.

Methods: A case finding study was conducted to identify types of health and social care use and data collection methods employed in previous studies with this population. Based on this evidence, resource use questionnaires for completion by GP staff and interviewer-administered participant questionnaires (covering a wider cost perspective and health-related quality of life) were tested within a feasibility RCT. Interviewer-administered questionnaires included the EQ-5D-3L (the NICE recommended measure for use in economic evaluation). Participants were adults > 18 years with a mild or moderate learning disability and type 2 diabetes, with mental capacity to give consent to research participation.

Results: Data collection for questionnaires completed by GP staff requesting data for the last 12 months proved time intensive and difficult. Whilst 82.3% (121/147) of questionnaires were returned, up to 17% of service use items were recorded as unknown. Subsequently, a shorter recall period (4 months) led to a higher return rate but with a higher rate of missing data. Missing data for interviewer-administered participant questionnaires was > 8% but the interviewers reported difficulty with participant recall. Almost 60% (48/80) of participants had difficulty completing the EQ-5D-3L.

Conclusions: Further investigation as to how service use can be recorded is recommended. Concerns about the reliability of identifying service use data directly from participants with a learning disability due to challenges in completion, specifically around recall, remain. The degree of difficulty to complete EQ-5D-3L indicates concerns regarding the appropriateness of using this measure in its current form in research with this population.

Trial Registration: Current Controlled Trials ISRCTN41897033 (registered 21 January 2013).
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http://dx.doi.org/10.1186/s40814-018-0266-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5911950PMC
April 2018

The evaluation of enhanced feedback interventions to reduce unnecessary blood transfusions (AFFINITIE): protocol for two linked cluster randomised factorial controlled trials.

Implement Sci 2017 07 3;12(1):84. Epub 2017 Jul 3.

Transfusion Medicine, NHS Blood and Transplant, Oxford, UK.

Background: Blood for transfusion is a frequently used clinical intervention, and is also a costly and limited resource with risks. Many transfusions are given to stable and non-bleeding patients despite no clear evidence of benefit from clinical studies. Audit and feedback (A&F) is widely used to improve the quality of healthcare, including appropriate use of blood. However, its effects are often inconsistent, indicating the need for coordinated research including more head-to-head trials comparing different ways of delivering feedback. A programmatic series of research projects, termed the 'Audit and Feedback INterventions to Increase evidence-based Transfusion practIcE' (AFFINITIE) programme, aims to test different ways of developing and delivering feedback within an existing national audit structure.

Methods: The evaluation will comprise two linked 2×2 factorial, cross-sectional cluster-randomised controlled trials. Each trial will estimate the effects of two feedback interventions, 'enhanced content' and 'enhanced follow-on support', designed in earlier stages of the AFFINITIE programme, compared to current practice. The interventions will be embedded within two rounds of the UK National Comparative Audit of Blood Transfusion (NCABT) focusing on patient blood management in surgery and use of blood transfusions in patients with haematological malignancies. The unit of randomisation will be National Health Service (NHS) trust or health board. Clusters providing care relevant to the audit topics will be randomised following each baseline audit (separately for each trial), with stratification for size (volume of blood transfusions) and region (Regional Transfusion Committee). The primary outcome for each topic will be the proportion of patients receiving a transfusion coded as unnecessary. For each audit topic a linked, mixed-method fidelity assessment and cost-effectiveness analysis will be conducted in parallel to the trial.

Discussion: AFFINITIE involves a series of studies to explore how A&F may be refined to change practice including two cluster randomised trials linked to national audits of transfusion practice. The methodology represents a step-wise increment in study design to more fully evaluate the effects of two enhanced feedback interventions on patient- and trust-level clinical, cost, safety and process outcomes.

Trial Registration: http://www.isrctn.com/ISRCTN15490813.
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http://dx.doi.org/10.1186/s13012-017-0614-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5496161PMC
July 2017

Evaluating the effectiveness and cost-effectiveness of Dementia Care Mapping™ to enable person-centred care for people with dementia and their carers (DCM-EPIC) in care homes: study protocol for a randomised controlled trial.

Trials 2016 06 24;17(1):300. Epub 2016 Jun 24.

School of Dementia Studies, University of Bradford, Bradford, BD7 1DP, UK.

Background: Up to 90 % of people living with dementia in care homes experience one or more behaviours that staff may describe as challenging to support (BSC). Of these agitation is the most common and difficult to manage. The presence of agitation is associated with fewer visits from relatives, poorer quality of life and social isolation. It is recommended that agitation is treated through psychosocial interventions. Dementia Care Mapping™ (DCM™) is an established, widely used observational tool and practice development cycle, for ensuring a systematic approach to providing person-centred care. There is a body of practice-based literature and experience to suggests that DCM™ is potentially effective but limited robust evidence for its effectiveness, and no examination of its cost-effectiveness, as a UK health care intervention. Therefore, a definitive randomised controlled trial (RCT) of DCM™ in the UK is urgently needed.

Methods/design: A pragmatic, multi-centre, cluster-randomised controlled trial of Dementia Care Mapping (DCM™) plus Usual Care (UC) versus UC alone, where UC is the normal care delivered within the care home following a minimum level of dementia awareness training. The trial will take place in residential, nursing and dementia-specialist care homes across West Yorkshire, Oxfordshire and London, with residents with dementia. A random sample of 50 care homes will be selected within which a minimum of 750 residents will be registered. Care homes will be randomised in an allocation ratio of 3:2 to receive either intervention or control. Outcome measures will be obtained at 6 and 16 months following randomisation. The primary outcome is agitation as measured by the Cohen-Mansfield Agitation Inventory, at 16 months post randomisation. Key secondary outcomes are other BSC and quality of life. There will be an integral cost-effectiveness analysis and a process evaluation.

Discussion: The protocol was refined following a pilot of trial procedures. Changes include replacement of a questionnaire, whose wording caused some residents distress, to an adapted version specifically designed for use in care homes, a change to the randomisation stratification factors, adaption in how the staff measures are collected to encourage greater compliance, and additional reminders to intervention homes of when mapping cycles are due, via text message.

Trial Registration: Current Controlled Trials ISRCTN82288852 . Registered on 16 January 2014. Full protocol version and date: v7.1: 18 December 2015.
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http://dx.doi.org/10.1186/s13063-016-1416-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4921015PMC
June 2016

Supported self-management for adults with type 2 diabetes and a learning disability (OK-Diabetes): study protocol for a randomised controlled feasibility trial.

Trials 2015 Aug 8;16:342. Epub 2015 Aug 8.

Leeds Institute of Health Sciences, University of Leeds, Leeds, UK.

Background: Individuals with a learning disability (LD) are at higher risk of developing type 2 diabetes, but LD is not straightforward to define or identify, especially at the milder end of the spectrum, which makes case finding difficult. While supported self-management of health problems is now established, current material is largely educational and didactic with little that facilitates behavioural change. The interaction between the person with diabetes and others supporting their care is also largely unknown. For these reasons, there is considerable work needed to prepare for a definitive trial. The aim of this paper is to publish the abridged protocol of this preparatory work.

Methods/design: Phase I is a prospective case-finding study (target n = 120 to 350) to identify and characterise potential participants, while developing a standardised supported self-management intervention. Phase II is a randomised feasibility trial (target n = 80) with blinded outcome assessment. Patients identified in Phase I will be interviewed and consented prior to being randomised to (1) standard treatment, or (2) supported self-management. Both arms will also be provided with an 'easy read' accessible information resource on managing type 2 diabetes. The intervention will be standardised but delivered flexibly depending on patient need, including components for the participant, a supporter, and shared activities. Outcomes will be (i) robust estimates of eligibility, consent and recruitment rates with refined recruitment procedures; (ii) characterisation of the eligible population; (iii) a standardised intervention with associated written materials, (iv) adherence and negative outcomes measures; (v) preliminary estimates of adherence, acceptability, follow-up and missing data rates, along with refined procedures; and (vi) description of standard treatment.

Discussion: Our study will provide important information on the nature of type 2 diabetes in adults with LD living in the community, on the challenges of identifying those with milder LD, and on the possibilities of evaluating a standardised intervention to improve self-management in this population.

Trial Registration: Current Controlled Trials ISRCTN41897033 (registered 21 January 2013).
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http://dx.doi.org/10.1186/s13063-015-0832-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4529698PMC
August 2015

Lifestyle referral assessment in an acute cardiology setting: study protocol for a randomized controlled feasibility trial.

Trials 2013 Jul 11;14:212. Epub 2013 Jul 11.

Leeds Institute of Health Sciences, University of Leeds, Leeds, UK.

Background: Lifestyle and behaviour change are important factors in the prevention of cardiovascular disease and reduction of premature mortality. Public health initiatives have focused on opportunities for healthcare staff to deliver lifestyle advice routinely in primary and secondary care but there is no consistent approach to onward referrals and the rate of uptake of advice remains low. We do not know if advice is more effective in supporting behaviour change when a systematic approach is taken that includes identification of barriers to change, directing patients toward services, referral to services, and feedback on outcome.

Methods And Design: This is a single-centre, randomized, unblinded feasibility trial in an acute hospital setting which aims to assess the feasibility of a definitive trial and provide proof of concept for the systematic delivery of individualized lifestyle advice in patients managed through an acute cardiology in-patient service.Patients will be recruited before discharge and randomized to two groups. A control group will receive the usual lifestyle assessment and referral, while an intervention group will receive the usual assessment plus the new individualized lifestyle assessment and referral. The new assessment will inform assignment of each patient to one of three categories based on personal barriers to change. Patients may be referred to a formal lifestyle-change programme, through the 'Leeds Let's Change' website, or they may be guided in self-management, using goal setting, or they may be assigned to a 'deferment' category, for reassessment at follow-up. These latter patients will be given a contact card for the 'Leeds Let's Change' service.

Discussion: Lifestyle change is an important mechanism for improving health and wellbeing across the population but there are widely acknowledged difficulties in addressing lifestyle factors with patients and supporting behaviour change. A systematic approach to assessment would facilitate audit and provide an indicator of the quality of care. The new assessment template has been designed to be quick and easy to use in practice and could, for example, be added to a primary care consultation or form part of a nursing discharge assessment in an acute setting.

Trial Registration: Current Controlled Trials ISRCTN41781196.
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http://dx.doi.org/10.1186/1745-6215-14-212DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3710506PMC
July 2013